Safety hook



Nov. 9, 1937. E. RODENBACH SAFETY HOOK Filed Nov. 10, 1936 INVENTOR Frrzsi Bode/z ac/z ATTORNF'Y Patented Nov. 9, 1937 UNITED STATES PATENT Fi 3 Claims.

This invention relates to safety hooks of the type provided with automatically self-closing tongues.

The principal object of this invention is to provide in such safety hook a positively operating self-closing tongue, which may be entirely depended upon and wherein the working parts are unlikely to be damaged or broken.

Another object of this invention is to provide in connection with such hook, a self-closing snap tongue which is relatively light in weight, to assure instantaneous operation, while at the same time it is strong and durable in construction.

A further object of this invention is to provide within such safety hook, spiral spring means, of

relatively long dimension, designed to withstand continuous and positive operation for long periods of time without deterioration and without the necessity of exchanging them due to breakage.

A further object of this invention is to so construct and arrange said spring means that the latter becomes more compressed and under greater tension as the tongue is swung inwards, causing the tongue to be propelled much faster from its inward position to its outward, locking position.

A still further object of this invention is to provide at the free ends of the hook and the tongue, means for interlocking the two parts of the hook when in closed position.

The foregoing and still other objects and advantages of this invention will become more fully apparent from the ensuing description in connection with the accompanying drawing, which latter forms an essential part of this disclosure, but by no means are intended to limit same to the actual showing, and in which Fig. 1 is a plan View of the presently preferred form of my device;

Fig. 2 is a detailed side elevation, partially broken off, of the tongue of my device;

Fig. 3 is an end elevation thereof, partially in section;

Fig. 4 is a bottom end view of Fig. 3;

Fig. 5 is a top view of the hinge .end of the hook body;

Fig. 6 is a side elevation thereof; and

Fig. 7 represents side and front elevations of the spring support used in my device.

Referring now specifically to the drawing, numeral H denotes a body of the hook which may be shaped in any convenient manner to suit specific purposes. Hingedly connected at H to the hook body is a tongue I2, which is shown in its looking or closed position in full lines in Fig. 1,

and which is also shown in that figure partially in broken lines and partially in full lines, and in section, in its swung-in unlocking position.

The free ends of the hook body and of the tongue are provided with an interlocking arrangement, indicated, respectively, at l3 and M. The body of the tongue is substantially hollow and preferably of tubular construction, and with a spacious interior, as indicated at l5. The hinge end of the tongue is slotted at It, and is provided with apertures I! for receiving a pivot.

The hinge end of the hook body consists of a reduced portion l8, with a corresponding aperture. 99. The upper .edge of reduced portion I 8 is especially shaped, as clearly seen in Fig. 6, and is provided with a notch 20, which is disposed eccentrically to the axis of aperture l9. Within the hollow interior of tongue l2, there is disposed a spiral spring Zl, which is held under compression within the tongue. The end of the spring, nearest to the hinge connection between the hook body and the tongue, rests against the spring support 22, shown in detail in Fig. '7, and which spring support consists of a spring receiving end 23, and a broadened end 24, which latter possesses a sharp lower edge 25. This edge is adapted to engage notch 26 of reduced portion !8. Spring support 22 is adapted to swing with the movement imparted to spring 2!, when the latter is brought under tension.

Spring M is of considerably lesser peripheral dimension than the hollow interior of tongue l2, so as to permit the spring to bodily flex within the tongue when brought under excessive tension, as indicated in broken lines in Fig. 1. It is to be noted that spring 2! is relatively long as compared with its outer diameter.

Referring now particularly to Fig. 1., it will be seen that due to the disposition of notch 2E3 in eccentric relation to pivot H, the inward swing of tongue l2 will cause the compression of spring 2i, whereby the latter is brought under constantly increasing additional tension as tongue l2 travels from its interlocking position inwards. The degree of compression of the spring may be clearly judged from are 1, indicated in Fig. 1, the center of which are corresponds to the bottom edge of notch 20.

Spring 2!, when originally placed into tongue I2, is held therein under tension. When now that spring is brought under additional tension by the swinging-in of tongue !2, the spring will increase its tendency of reverting to its erstwhile position and thereby assure the back snap of tongue I2 to its interlocking position with the hook body. The additional compression of the spring is indicated in an exaggerated fashion by the curvature or flexing of the spring in the broken line position of the tongue in Fig. 1.

Due to the length and the arrangement of the eccentrically supported spiral spring, an overstrain of the latter is entirely eliminated so that the possibility of breakage is reduced to a minimum, whereby the life and operation of the device becomes practically unlimited.

While I have shown a specific form of my invention, be it understood that the construction of the safety hook may be altered to meet various special conditions, and I therefore reserve for myself the right to make such alterations and changes as may become necessary, without departing from the broad scope of my idea, as set forth in the annexed claims.

I claim:

1. In a safety hook, a hook body and a tongue hingedly interconnected with one another, said tongue comprising a. hollow, tubular member, a relatively long, spiral spring undercompression within said tongue, the outer diameter of said spring being considerably smaller than the interior diameter of said hollow member for permitting a bodily flexing of the spring within the latter, a support for the spring end nearest to the hinge connection between said hook body and said tongue and engaging a fixed point disposed eccentrically relative to the axis of the hinge connection, said support being free to swing within said tongue.

2. In a safety hook, a hook body and a tongue hingedly connected with one another, the hingeend of said body comprising a reduced portion having an aperture for receiving a hinge pin, said reduced portion providedwith a notch disposed eccentrically relative to said aperture, said tongue comprising a hollow tubular member, having a relatively spacious interior, and being provided with a slotted, apertured hinge-end in engagement with the reduced portion of said hook body, a relatively long spiral spring, of a relatively small outer diameter, under pressure disposed within said tongue, a spring support having a sharp, broadened end-edge in engagement with said notch of the reduced body portion and being free to swing within said tongue, and means at the free end of the hook body, and corresponding means at the free end of said tongue, for interlocking the latter with the hook body.

3. In a safety hook, a hook body and a tongue hingedly interconnected with one another, said tongue comprising a hollow member, its hollow, cylindrical portion extending over substantially the entire length of said member, a spiral spring, normally under compression, disposed within said hollow portion and extending over substantially the entire length thereof, the exterior peripheral dimension of said spring being considerably less than the interior peripheral dimension of the hollow portion, the end of the said spring nearest to the hinge connection between said hook body and said tongue bearing against a fixed point disposed eccentrically relative to the axis of the hinge connection, the other end of the spring bearing against the closed end of the tongue at a point substantially diagonally opposite to said fixed point, which disposition of the spring causes it to bodily flex within the hollow portion of the tongue, when the latter is forced inwards and the spring is thereby brought under increased compression.

ERNST RODENBACH. 

